Sealing device



N. A. CHRISTEN SEN May 31, 1949.

SEALING DEVICE Original Filed May 26, 1945 .J M M M /N N on VE 0 NT MT RA H C W P .5 L F N M .Y B UQM w\ I Patented May 31, 1949 2,471,933SEALING DEVICE Niels A. Christensen, South Euclid, Ohio Originalapplication May 26, 1943, Serial No. 488,530. Divided and thisapplication April 12, 1945, Serial No. 587,981

1 Claim. (01. 285-154) This application is a division of my applicationSerial No. 488,530, filed May. 26, 1943, for an Accumulator, now Patent2,406,197.

The general object of this invention is to provide an eiiective sealbetween a pair of coacting disconnectable members which are relativelystationary in use and where the joint between the members is subjectedto fluid pressure. It is an object of the invention to provide such aseal in a very simple form which shall be effective in service anddurablein use.

A further object of the invention is to provide an efiicient sealbetween two members screwthreaded together, which seal shall not beliable to be abraded or injured by the relative rotation of the membersin tightening the joint or by subsequent separation and rejoining of theparts.

My invention is well adapted, for instance, for sealing the connectionbetween a cylinder head and a cylinder, or between a removable conduitand a chamber to which it is connected, or between various members, oneof which is screwed into the other. The invention is hereinafter morefully described in connection with the illustrative embodiment shown inthe drawings and the essential novel features are summarized in theclaim.

In the drawings, Fig. 1 is a longitudinal section through an accumulatorequipped with several of my seals at various locations; Fig. 2 is across section of such accumulator in a radial plane indicated by theline 2--2 on Fig. 1; Fig. 3 is a fragmentary section taken radiallythrough the sealing ring of this invention; Fig. 4 is an enlarged crosssection of the seal shown at the admission end of the accumulator.

I will first describe briefly, the accumulator shown by way of examplein Figs. 1 and 2. Such accumulator comprises a cylinder III which hasend walls H and 12, each of which has a passageway designated 13 and M,respectively, through which fluid may be admitted to the cylinder. Aconduit 15 is attached to one end of the cylinder for communication withthe passageway l3, while another conduit I6 is attached to the other endfor communication with the passageway It. In practice, air underpressure is forced into the cylinder through the conduit l5 and is heldtherein by means of a check valve, such as that used in an automobiletire and indicated at 17, while the conduit I6 is connected to thehydraulic system with which the accumulator is intended to be used.

A movable partition in the form of a piston 20 is shown within thecylinder, the same being guided by a stem 2| which projects into themember 22 which forms the end wall l2. Preferably, such member acup-like structure having a substantially cylindrical wall portion 23which is adapted to extend into the cylinder and to be in threadedengagement therewith. The member may also have an extension 24 whichprojects into the cylinder and which functions to guide the piston rodas aforesaid. An outer extension 25 is arrangedior receiving the conduit16 and has sufficient length that when the piston reaches the end of itsavailable movement toward the conduit l6, as indicated by the brokenlines 20A, the end 26 of the piston rod will clear the end of the nipple21 which is utilized for connecting the conduit l6 tothe extension 25.Similarly, the, inner extension 24 is sufilciently long that when thepiston is at the limit of its travel toward the conduit 1 5, asindicated by the broken line 20-3, the end of the piston rod is stilldis posed within the extension 24.

The cylinder described may be supported in any convenient manner, butfor purpose of illustration I have shown a supporting plate 40 clampedbetween the cylinder head 22 and the end of the cylinder wall Ill. Thecylinder head 22 and the nipples 21 and M, are each mounted in therespective carrying portion of the device by being screw-threadedtherein as shown in Fig. 1. Such screw thread is not fluid tight but myseal, about to be described, renders the joint between the respectivemembers perfectly tight.

To seal the gas and'liquid chambers where the cylinder head joins thebody of the cylinder, as well as the conduits shown as connected to thecylinder heads, I utilize the sealing element of this invention. Thiselement comprises an annular packing ring which may be made of solidrubber or a synthetic composition which is very dense and which yetpossesses considerable liveliness and elasticity. Such ring is circularin the plane of the ring and prior to the assemblage has a circularcross section, as indicated at 30 in Fig. 3.

The outer periphery of the sealing ring is normally slightly larger thanthe bore of the annular wall against which such outer periphery seats.The depth of the groove occupied by the ring is less than thecross-sectional diameter of the unapplied ring, but has a width greaterthan the major axis of the applied ring, as shown in Fig. 4.

Accordingly, when the ring is put in place it is compressed into asubstantially ellipsoidal cross section, as indicated at 30--A, till-Band 30-0 in Fig. 1, and shown in larger scale in Fig. 4. This detailshows the particular ring 3ll--B but force it against the far wall ofthe groove. 0n

the other hand, upon a reductions-in;.pressurein the cylinder the ringby its own elasticity works back toward its positionsagain'st theopposite-= wall of the groove. This movement 'ofthe yielding ring keepsit alive and pliable so that it is effective for a very long period oftime.

In the particular embodiment shown in Fig. 1, air under..pre ssure..-is"forced-into. the cylinder throughwtheflconduitilfipfwhile. oil underpressureis .forcedintothe, cylinder through the con- .duit. lfigpassageway "Ifilland ,o'blique; passageway 43,.untily.the,pressuresreach'thejdesired operat- ,ing. a degree. "Inc. amount. of air. injectedis such that lwhenthesysteni islnormally ready. for operation. thepiston. 20. "ispositionedl approximately at .themid-portion jofl the.cylinder. "The. source .of...air .mayl thengbea disconnected, While that.pumpedintoflthe pynnden is retained therein by the checkvali efl'l,.The,.airZ thus provides a source of potentialaenerg y for forcing 011within the. oylindercinto. the. system. whenever demand for itoccurslduningfluse.

vary. in .use, .which. producesfjthe desired knead- .ingeffect.ontheapacking rings.

ilt-shouldbe articui rlynoted that in each ing Thus-theactu'al'pressures .on,oppo'site-. sides. of the. piston continuallystance of my sealing. ring shown atSD-A; 30 B .and 30-43, the ring isentirelyind ependent of.the

two :metal' surfacesrwhichare, caused to abut each other when the screwthreaded member (22, 4|, 2'!) is turned into final position. Hence thering is entirely free from the abrading action of such surfaces whichheretofore has frequently injured a gasket interposed between them. Thisrelief from clamping strain on the packing material itself increases thelife of thepackingand at the same time'the packingisissfre forzkneadingmovement to maintain it active, and thus further prolong its life.

I claim:

.Thescombination of a hollow member adapted .to .contain ,fiuid underpressure, a member attached thereto and stationary therewith, said imemhenhavinglarecess opening outwardly theretram aw packingielement inthe recess and comprising aresilient ring normally substantiallycircular in cross-section, and acting alone in the recess, the depth ofthe-recess being smaller than the normal cross-sectional diameter of therin wherebyithe ring is :djeformed into: an-' ellipsoidal cross-section,1the recess-having a "width greater than the longest cross' 'sectionaldimension-ofthe deformed 'ringywh'er'eby thering may be shifted therecess by-fluid pressure in the" hollow memher, anda -coupling"member"extending through said ring and-having a threaded connection with saidfirst=mentioned member.

NIEIESA. 'GHRISTENSEN.

REFERENCES vcruel) .Thefollowing, referencesare of record in the file orthis patent:

UNITED STATES? PATENTS "Number Name Date 2,187,217 'Winslow',Jan.16,:-l940 ""2,349;170' Jackman May 16, 1944 2394364 Christensen Feb.-5,"1946 .11) 2,420,104 Smith May s, 1947

